Definition of 'Blue Collar'
A working-class person historically defined by hourly rates of pay and manual labor. A blue collar worker refers to the fact that most manual laborers at the turn of the century wore blue shirts, which could hold a little dirt around the collar without standing out.
This working class stands in contrast to white collar workers, which historically have had the higher-paying, salaried positions to go with their clean and pressed white shirts.
Investopedia explains 'Blue Collar'
The term blue collar has in the past implied a certain lack of worker education as well, but those lines are blurred today. Today blue collar workers can be formally educated, skilled and highly paid. They can also earn more annually then some of their white collar counterparts.
The rate of college attendance in the U.S. has skyrocketed in the past 100 years, democratizing the education level once reserved for only wealthy families. Blue collar work does not typically carry a negative connotation in the United States, and has in fact been a source of multi-generational pride for millions, especially in the geographic northeast, where most of country's heavy industry first developed over 150 years ago.